Coupling arrangement for a compressed-gas circuit breaker equipped with a hydraulic drive

ABSTRACT

A coupling arrangement is provided for a compressed-gas circuit breaker such as a high-voltage power breaker or the like having a contact system mounted in a gas-containing enclosure. An actuator rod connected to the contact system actuates the same and has a plunger portion extending from the enclosure. The plunger portion in turn is operated by a hydraulic drive having a piston rod. The coupling arrangement includes a coupling for connecting the plunger portion to the piston rod of the hydraulic drive and an air-filled housing for receiving the coupling therein. The housing is arranged between the hydraulic drive and the enclosure.

United States Patent 1191 Beier et a1.

[ Dec. 23, 1975 COUPLING ARRANGEMENT FOR A COMPRESSED-GAS CIRCUIT BREAKER EQUIPPED WITH A HYDRAULIC DRIVE [75] Inventors: Helmut Beier; Dieter Noack, both of Berlin, Germany [73] Assignee: Siemens Aktiengesellschaft, Munich,

Germany [22] Filed: Apr. 2, 1974 [21] Appl. No.: 457,233

[30] Foreign Application Priority Data Apr. 4, 1973 Germany 2317499 [52] US. Cl. 200/82 B; 403/336; 200/148 B; 200/153 V [51] Int. Cl. HOlI-I 35/38 [58] Field of Search 403/337, 336, 335; 200/82 B, 148 R, 148 B, 153 V [56] References Cited UNITED STATES PATENTS 2,181,537 11/1939 Schmitter 403/335 2,404,385 7/1946 Fritts 403/336 2,500,429 3/1950 Nijland 200/153 v 2,868,576 1/1959 Boughton 403/336 3,076,081 1/1963 Oppel 200/82 B 3,336,453 8/1967 Beatty et a1. 200/82 13 Primary Examiner-Gerald P, Tolin Attorney, Agent, or FirmKenyon & Kenyon Reilly Carr & Chapin [5 7] ABSTRACT includes a coupling for connecting the plunger portion to the piston rod of the hydraulic drive and an airfilled housing for receiving the coupling therein. The housing is arranged between the hydraulic drive and the enclosure.

6 Claims, 5 Drawing Figures US. Patent Dec. 23, 1975 Sheet10f4 3,928,738

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U.S. Patent Dec. 23, 1975 Sheet3of4 3,928,738

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U.S. Patent Dec.23, 1975 Sheet40f4 3,928,738

COUPLING ARRANGEMENT FOR A COMPRESSED-GAS CIRCUIT BREAKER EQUIPPED WITH A HYDRAULIC DRIVE BACKGROUND OF THE INVENTION The invention relates to a coupling arrangement for a compressed gas circuit breaker such as a high-voltage power circuit breaker or the like equipped with sealed gas chambers for the gas which functions as a quenching and insulation medium and with a dual-action hydraulic drive for controlling the contact system.

2 therein within the scope and the range of the claims. The invention, however, together with additional objects and advantages will be best understood from the following description and in connection with the accompanying drawings.

In such switching devices, it is desirable to let the driving power providedby the hydraulic drive act directly on the contact systems to thereby .avoid space consuming kinematic reversing and lever mechanisms. For the case of high-voltage switches, this means a coupling as direct as possible of the preferably grounded drive with an insulating actuator element which opens or closes the contact arrangement operating at an electric potential. This actuator element is located in the gas enclosure of the breaker and is brought out from the gas enclosure by means of a gastight bushing. The actuator element is coupled to the drive to avoid losses due to leakage of the gaseous quenching and insulation medium which can be especially sulphur hexafluoride.

SUMMARY OF THE INVENTION It is an object of the invention to provide a coupling arrangement for a circuit breaker of the kind referred to above wherein a close coupling is achieved between the hydraulic drive and the actuating member of the breaker. Subsidiary to this object, it is an object of the invention to provide such a coupling arrangement so that in the event of a leak in the gastight bushing, no hydraulic liquid of the drive can penetrate into the gas containing enclosure and thereby adversely influence the insulation properties of the compressed gas. On the other hand, the penetration of insulating gas into the hydraulic system should be prevented when the hydraulic drive is not under pressure.

The objects are realized in the coupling arrangement according to the invention by the feature that between the gas enclosure of the breaker and the drive an airfilled intermediate housing is placed which serves to receive a coupling which connects the piston rod of the drive with a plunger for actuating the contact system. According to another feature of the invention, the air-filled intermediate housing is configured to accommodate a switch position indicator which is preferably mechanically developed. The coupling can be rigidly coupled with the indicating element of the switch position indicator. Furthermore, it is possible to provide the coupling with an extension for a manually actuated apparatus which is attached at the intermediate housing. In an especially advantageous embodiment, the coupling arrangement can consist of two ring components which can be mutually placed under tension and are axially displaceable, one of these being positively connected with the plunger portion and the other with the piston rod.

Although the invention is illustrated and described herein as a coupling arrangement for a compressed-gas circuit breaker equipped with a hydraulic drive, it is nevertheless not intended to be limited to the details shown, since various modifications may be made BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic diagram, partially in section, of a compressed-gas circuit breaker equipped with a coupling arrangement according to the invention.v

FIG. 2 illustrates details of the coupling arrangement according to the invention.

FIG. 3 shows details of the coupling according to a subsidiary emobdiment of the invention wherein ring members are provided at the piston rod and the plunger portion respectively.

FIG. 4 is a schematic diagram showing how the indicating memberof an indicating device of the coupling arrangement is rigidly connected to the coupling in the air-filled housing.

FIG. 5 illustrates how the coupling arrangement can be equipped with a hand operated device for manually actuating the contact systems of the breaker.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION The compressed-gas circuit breaker depicted in FIG. 1 can be configured as a high-voltage power circuit breaker according to the dual pressure principle, as well as the blast piston principle. In both cases, a gas such as sulphur hexafluoride is used asthe quenching and insulation medium. The gas is under a pre-determined pressure of 4 to 10 bar for example. Reference numeral 1 designates the compressed-gas circuit breaker in its entirety.

The breaker includes two axially arranged switching chambers 2 and 3Iwherein two contact systems, connected in series, are housed. Thecontact systems can be actuated simultaneously. The switching chambers 2 and 3 which contain the contact systems are attached to a gearing head 4 which is maintained at high-voltage potential. The gearing head 4 is mounted on a vertical supporting insulator 5 having an interior 7 wherein a moveable actuator rod 6 is located for actuating the contact systems. The rod 6 is made of insulating material. In the interior of the insulator 5, the gaseous insulating medium such as sulfur hexafluoride is also located so that the actuator rod 6 has to be carried through the wall 13 of the gas containing enclosure of the compressed-gas circuit breaker l by means of a gastight bushing 14.

A gastight feedthrough of the type designated by reference numeral 14 is disclosed in the United States patent application of Gerhard Thurk and Reinhard Lekar entitled: Gastight Feedthrough which is based on patent application No. P 23 15 732.6 filed on Mar. 27, 1973 in the Federal Republic of Germany.

The supporting insulator 5 is in turn supported by an air-filled intermediate housing 8 wherein an indicator device 9 for indicating the switch position of the breaker is located. The free end 12 of the actuator rod 6 extends through the wall 13 and is configured as a plunger which terminates in the interior of the intermediate housing 8. The free end 15 of the piston rod 16 which belongs to a drive system is rigidly coupled to the free end 12 of rod 6.

The intermediate housing 8 is supported by a base pedestal 10. Drive 11 is flange-connected to the under 3 side of the intermediate housing 8.

As shown by FIG. 2, the piston rod 16 of a hydraulic drive 11 operating at high pressure is coupled by means of a coupling 18 to the plunger portion 12. The piston rod 16 is led into the interior of the housing 8 by means of a pressuretight bushing 19 which in operation, is impermeable to the liquid. The operation of the compressed-gas circuit breaker is not adversely affected by oil pouring out in the event of a leak because the gastight bushing 14 prevents a penetration of hydraulic liquid into the gas region 7 of the electric compressedgas circuit breaker.

The coupling 18 consists of two rings 18a and 18b, which can be mutually placed under tension and are connected together by screw elements 20, and which are axially displaceable against each other. In this manner, a center displacement of the plunger portion 12 and the piston rod 16 can easily be equalized. The ring part 180 is connected in a force-tight manner with the plunger portion 12, and the ring portion 18b is connected in a force-tight manner with the piston rod 16.

FIG. 3 shows details of the coupling means for coupling the ring members 18a and 18b so as to permit the ring members to be axially displaceable with respect to each other.

Coupling 18 is engaged by a lever 21, which is rigidly coupled to the indicating element of the indicator device 22 for indicating switch position. Details of this connection are shown in F IG. 4.

The construction of the arrangement according to the invention makes it possible to provide the coupling 18 with an extension 31 for a manually operated actuation means 30 which can be mounted at 23 of the intermediate housing as shown in FIG. 5.

What is claimed is:

1. In a compressed-gas circuit breaker such as a highvoltage power breaker or the like, the breaker including: a closed gas circuit for gas utilized as an arcquenching and insulatingmedium; an enclosure containing the gas; a contact system mounted in the enclosure; an actuator rod connected to the contact system for actuating the same, the actuator rod having a plunger portion extending from the enclosure; and, a

hydraulic drive containing a hydraulic fluid and having a piston rod connected to the plunger portion of the actuator rod for actuating the contact system, the improvement of a coupling arrangement comprising: an air-filled housing containing the plunger portion and the piston rod therein; a coupling connecting the plunger portion directly to the piston rod in said housing; and, a gas-tight bushing on said housing surrounding the plunger portion for facilitating the penetration of the plunger portion into said housing from the enclosure in a gas-tight manner; said housing being disposed directly between the enclosure and the hydraulic drive whereby hydraulic fluid from the hydraulic drive is prevented from penetrating the gas containing enclosure in the event of a failure of said bushing.

2. The coupling arrangement of claim 1 wherein the coupling is movable between two positions corresponding to the open and closed positions, respectively, of the contact system, said coupling arrangement comprising an indicator device connected to said coupling indicating the position of the contact system.

3. The coupling arrangement of claim 2, said indicator device being mounted on said housing.

4. The coupling arrangement of claim 2, said indicator device having an indicating member indicating the position of the contact system, rigid connecting means for rigidly connecting said coupling to said indicating member.

5. The coupling arrangement of claim 1 comprising an extension member connected to said coupling, and manually operated actuation means fixedly mounted on said air-filled housing and connected to said extension member for manually moving said coupling between two positions corresponding to the open and closed positions of the contact system respectively.

6. The coupling arrangement of claim 1, said coupling including first and second ring members tensionable with respect to each other and connected forcetight to the plunger portion and the piston rod respectively, and coupling means for coupling said ring members so as to permit said ring members to be axially displaceable with respect to each other. 

1. In a compressed-gas circuit breaker such as a high-voltage power breaker or the like, the breaker including: a closed gas circuit for gas utilized as an arc-quenching and insulating medium; an enclosure containing the gas; a contact system mounted in the enclosure; an actuator rod connected to the contact system for actuating the same, the actuator rod having a plunger portion extending from the enclosure; and, a hydraulic drive containing a hydraulic fluid and having a piston rod connected to the plunger portion of the actuator rod for actuating the contact system, the improvement of a coupling arrangement comprising: an air-filled housing containing the plunger portion and the piston rod therein; a coupling connecting the plunger portion directly to the piston rod in said housing; and, a gas-tight bushing on said housing surrounding the plunger portion for facilitating the penetration of the plunger portion into said housing from the enclosure in a gas-tight manner; said housing being disposed directly between the enclosure and the hydraulic drive whereby hydraulic fluid from the hydraulic drive is prevented from penetrating the gas containing enclosure in the event of a failure of said bushing.
 2. The coupling arrangement of claim 1 wherein the coupling is movable between two positions corresponding to the open and closed positions, respectively, of the contact system, said coupling arrangement comprising an indicator device connected to said coupling indicating the position of the contact system.
 3. The coupling arrangement of claim 2, said indicator device being mounted on said housing.
 4. The coupling arrangement of claim 2, said indicator device having an indicating member indicating the position of the contact system, rigid connecting means for rigidly connecting said coupling to said indicating member.
 5. The coupling arrangement of claim 1 comprising an extension member connected to said coupling, and manually operated actuation means fixedly mounted on said air-filled housing and connected to said extension member for manually moving said coupling between two positions corresponding to the open and closed positions of the contact system respectively.
 6. The coupling arrangement of claim 1, said coupling including first and second ring members tensionable with respect to each other and connected force-tight to the plunger portion and the piston rod respectively, and coupling means for Coupling said ring members so as to permit said ring members to be axially displaceable with respect to each other. 